AB0420 UNINTENTIONAL MONOTHERAPY IN RHEUMATOID ARTHRITIS PATIENTS RECEIVING TOFACITINIB AND DRUG SURVIVAL RATE OF TOFACITINIB
Authors: N. Inanc, K. Abacar, M. A. Ozturk, A. Tufan, H. Karadeniz, İ. Sari, G. Can, Y. Erez, Y. Pehlivan, E. Dalkiliç, T. Ocak, A. Cefle, A. Yazici, A. Senel, S. Akar, E. Durak Ediboglu, S. S. Koca, R. Piskin Sagir, S. Yilmaz, S. Gulcemal, Ö. Soysal Gündüz, C. S. Başibüyük, S. Alkan, T. Y. Cesur, F. Onen
Journal: Annals of the Rheumatic Diseases (2022)

Background Combination of MTX with a bDMARDs or tsDMARDs is considered the most effective treatment regimen currently available for patients with RA who have failed to respond to conventional DMARDs. However, approximately 30% of patients receive bDMARDs as monotherapy in daily clinical practice. Studies in the literature do not assess unintentional monotherapy in general. However, it is thought that some patients may switch to monotherapy unintentionally. In other words, some patients who are prescribed combination therapy switch to monotherapy without informing their physicians. Objectives To determine the rate of unintentional monotherapy in rheumatoid arthritis (RA) patients receiving tofacitinib and to evaluate tofacitinib survival rate. Methods This national, multicentre, retrospective study included patients’ data from the TURKBIO Registry. Data on demographics, clinical characteristics, disease duration and activity, comorbidities, and treatment were analysed. Results Data of 231 RA patients (84.8% female, median age, 56 years) were included; 153 were initially prescribed combination therapy and continued to their therapies; 31 were initially prescribed combination therapy but switched to monotherapy of their own will (unintentional monotherapy); 21 were initially prescribed monotherapy and switched to combination therapy; 26 were initially prescribed monotherapy and continued to their therapies. The combination and unintentional monotherapy groups did not differ regarding remission rate assessed by DAS28-CRP (60.5% and 70%, respectively, p=0.328). The rate of comorbidities at the time of data retrieval was significantly higher in the unintentional monotherapy group compared with the combination group (83.3% vs. 60.3%, p=0.031). Presence of comorbidities was a significant factor affecting switching to monotherapy (p=0.039, Odds ratio: 3.29, 95% CI: 1.06-10.18). Drug survival rates of the unintentional monotherapy and combination groups did not differ. The median drug survival duration of tofacitinib was 27+ months with a 1-year and 4-year drug survival rates of 89.6% and 60.2%, respectively, in the unintentional monotherapy group. Conclusion Although 13.4% of the study population started monotherapy unintentionally, drug survival rates of the unintentional monotherapy and combination groups were not different. Comorbidity was an important factor affecting transition from combination therapy to monotherapy. This study was sponsored by Pfizer. Figure 1. Disclosure of Interests Nevsun Inanc: None declared, Kerem Abacar: None declared, mehmet akif ozturk: None declared, Abdurrahman Tufan: None declared, Hazan Karadeniz: None declared, İsmail Sari: None declared, gercek can: None declared, Yesim Erez: None declared, yavuz Pehlivan: None declared, Ediz Dalkiliç: None declared, Tuğba Ocak: None declared, Ayse Cefle: None declared, Ayten Yazici Grant/research support from: Ayten Yazici has received project grant from Roche Pharmaceuticals, Turkey., Abdurrahman Senel: None declared, Servet Akar: None declared, Elif Durak Ediboglu: None declared, Süleyman Serdar Koca: None declared, Rabia Piskin Sagir: None declared, Sema Yilmaz: None declared, Semral Gulcemal: None declared, Özgül Soysal Gündüz: None declared, Canberk Sami Başibüyük Employee of: employee of Pfizer Pharmaceuticals, Istanbul, Turkey., Serdar Alkan Employee of: employee and shareholder of Pfizer Inc., Istanbul, Turkey., Teoman Yusuf Cesur Employee of: employee of Pfizer Pharmaceuticals, Istanbul, Turkey., Fatos Onen: None declared